Added 'DEBIAN_FRONTEND=noninteractive' to Dockerfile.
Minor comment tweaks.
Brought back `ES_PORT` publish flag to `make build`.
Minor Makefile updates.
Fixed exec indentation.
Removed `9200` and `9300` port forwarding in Vagrant file.
Added very simple test for embedded builds.
Merge pull request #21 from pblittle/feature/build-fixes-and-basic-test

Feature/build fixes and basic test